An electrical plug and receptacle relying on magnetic force from an electromagnet to maintain contact are disclosed. The plug and receptacle can be used as part of a power adapter for connecting an electronic device, such as a laptop computer, to a power supply. The plug includes electrical contacts, which are preferably biased toward corresponding contacts on the receptacle. The plug and receptacle each have a magnetic element. The magnetic element on one of the plug or receptacle can be a magnet or ferromagnetic material. The magnetic element on the other of the plug or receptacle is an electromagnet. When the plug and receptacle are brought into proximity, the magnetic attraction between the electromagnet magnet and its complement, whether another magnet or a ferromagnetic material, maintains the contacts in an electrically conductive relationship.